Davis said the Virginia-class submarine differs from other nuclear attack submarines because:

» It uses a propulsor instead of a regular propeller. A propulsor is an advanced-design propeller shielded by a duct.

» The nuclear reactor is fueled for the life of the ship (30-plus years).

» It has a nine-man airlock trunk, enabling an entire SEAL team to lock out together (instead of two at a time now).

» It has no periscope, using a photonics mast with a camera instead.

Winter also said that the Los Angeles-class submarine USS Buffalo would be sent to Guam next year.

The Navy's attack sub force of 53 is split almost evenly now, with 28 in the Atlantic and 25 in the Pacific. By 2010 there will be 31 nuclear-powered attack subs in the Pacific Fleet and 21 assigned to the Atlantic Fleet.